Hydrochemical characterization of groundwater quality using chemometric analysis and water quality indices in the foothills of Himalayas

Investigation of hydrochemical characteristic, water quality and associated health risks of metals and metalloids in water resources in the vicinity of Akamkpa quarry district, southeastern, Nigeria

Quarrying of rock aggregates generates produced water that, if not handled properly will be a source of pollution for nearby water bodies, thus affecting the chemistry of the water. This study examined the chemistry, impact of quarrying activities on water resources and the health consequences/risks posed by ingestion of the water by humans in the Akamkpa quarry region in southeastern Nigeria. Thirty (30) water samples consisting of pond water, stream water, hand dug wells, and borehole samples were collected and analyzed for their physicochemical parameters using standard methods. The results obtained from the analyses indicated that the water was moderately acidic, fresh, and not salty, with many parameters below the recommended standards with Ca2+, and HCO3- being the dominant ions present in the water resources. Rock weathering processes including silicate weathering as illustrated by hydrochemical facies, cross plots, and Gibbs diagrams are the dominant mechanisms influencing the quality and major ions chemistry of the water resources with minor contributions from dissolution, anthropogenic activities, and ion exchange. Ca-Mg-SO4-Cl and Na-K-HCO3- are the most important water types. Although the water quality index shows that the water is suitable for human use and irrigation, the mean values of As, Cd, Pb, and Se are above the acceptable limits. Additionally, the calculated contamination factor revealed the water resources are moderate to highly contaminated by As, Cd, Cr, Mo, Pb, Sb, and Se, and are therefore unsuitable for consumption with regards to these parameters. However, the residual sodium carbonate and water hazard index (WHI) values showed that 38% to 90% of sites in the quarry area were unsuitable for cultivation, 10-30% were in the low to medium impact category, and 60% were classified as risky and are from high to very high impact category. A non-cancer study of inhabitants living in the vicinity of the quarry area indicated that 6.7% of the sites have values greater than one, indicating that it may endanger the health of the people. Therefore, constant monitoring of the water quality is recommended as long-term use of contaminated water can harm humans, plants, and soils.

Assessment of potentially toxic elements in groundwater through interpolation, pollution indices, and chemometric techniques in Dehradun in Uttarakhand State

Providing safe drinking water for the entire world's population is essential for ensuring sustainable development. The presence of harmful compounds in aquifers, majorly toxic elements, is a serious environmental concern around the globe. This research aimed to quantify for the initial period the amounts of toxic elements in freshwater in the Dehradun Industrial Region of Uttrakhand, India, as well as the associated health risks. The PTEs (potentially toxic elements) Fe, Cd, Mn, Cu, Cr and Pb, Zn, Ni is measured by AAS and compared to BIS and WHO requirements for drinking safety. The order of mean trace element values in all groundwater samples were determined as Fe > Zn > Cu > Ni > Co > Cd > Pb. HPI was discovered to be higher than high class during the research period (HPI > 30), but under the severe contamination criterion of 100. Iron's MI and PI values were consistently over the threshold limit during the research period, and certain toxic elements were discovered exceptionally near the threshold limit, indicating a severe future influence on groundwater quality. According to PCA (principal component analysis), CM (correlation matrix), and potential health hazard, maximum levels of toxic elements in groundwater in the Dehradun region are attributed to land use patterns, anthropogenic activity, industrial activity, fertilizer and pesticide leaching, and residential waste into the aquifer system. The findings of this study could aid local planners and policymakers in preventing health risks from contaminated aquifers through the deployment of suitable monitoring and mitigation measures.

Heavy metal contamination assessment and potential human health risk of water quality of lakes situated in the protected area of Tisa, Romania

Protected areas are significant due to the high value of natural resources they shelter. This study's primary objective is to assess the quality status of the water resources (13 lakes and Tisa River) localized in the protected area of Tisa River on the territory of Romania. A number of 13 lakes and surface water (Tisa River) situated in the protected area through the Natura 2000 ecological network are studied. The chemistry and potential pollution status were analyzed by measuring and analyzing a set of twenty elements and sixteen physico-chemical parameters. The potential impact of anthropogenic activities was settled through the applied analysis and obtained results. A potential human health risk was noticed. Results indicated that waters are rich in Ni and Fe probably due to interaction with groundwater rich in Fe and Ni. Waters are characterized by potential contamination, which if directly or through the food chain consumed could negatively influence the human health. Piper and Gibbs plots indicated that the studied waters are divided into three categories based on water-rock interactions: mixed Ca2+-Na+-HCO3-, CaCO3-, and Na+-HCO3-. Likewise, the applied pollution indices (Heavy metal Pollution Index, HPI and Heavy metal Evaluation Index, HEI) indicated three pollution categories correlated to the As, Ni and Fe amounts. The findings of this research imply that the chemistry of the studied lakes and surface waters is influenced by the geogenic origin and emergence of anthropogenic activities. The significance of this research is related to understanding of mechanisms that influence the water quality, improving and conserving the natural water resources, and correspondingly understanding if any potential human health risks could be identified.

Tracing the land use specific impacts on groundwater quality: a chemometric, information entropy WQI and health risk assessment study

Understanding the nexus of land use and water quality can potentially underline the influences within the groundwater management. The study envisages land use-specific qualitative assessment of the groundwater resources in Ghaziabad district, in western Uttar Pradesh, India. For encountering the relative impacts of land use on the groundwater quality, chemometric analysis has been employed to apportion the pollution sources. The integration of quality parameters, in the information entropy index modeling, has segregated the quality classes and visualized the seasonal suitability trends as per potability standards along with non-carcinogenic health hazard risk assessment (HHRA). The qualitative assessment of the groundwater resources, along with spatial distribution, has deciphered a polluting impact, specifically in western and south western parts of district, and observed the linkages with direct and indirect discharges/seepages from densely populated residential and industrial land use types localized in urbanized areas. Statistically significant annual and seasonal variations have been found exclusively for EC, Mg2+, F-, Cd, Cr(total), Ni, and Pb which inferred variable concentrations, whereas land use types showed a non-significant variation within groundwater quality. Chemometric-based source apportioning and hierarchical cluster analysis (HCA) have derived salinization and enrichment of dissolved salts, arising from mixed sources and contributes to metal pollution, i.e., mainly from anthropogenic sources. Information EWQI derived poor to extremely poor category represented degraded potability specifically for fewer sites located within western and southern parts on the Yamuna-Hindon flood plains for limited sites of residential, industrial, and agricultural in an urbanized region. However, majority of the samples fall under excellent to good groundwater quality, recommendable in the north and north-eastern (peri-urban) regions. Non-carcinogenic HHRA has shown that majority of the samples categorized under unsafe value for hazard index (HI > 1), for females and children and thus, presumed probable health hazard risk from metal groundwater pollution in south-western part, eastern, and northern regions.

Evaluation of groundwater quality by adopting a multivariate statistical approach and indexing of water quality in Sagar Island, West Bengal, India

In the vicinity of the coast, predominantly groundwater is the sole reliable resource for potable purposes as the surface water sources are highly saline and unfit for human consumption. However, the groundwater in Sagar Island is highly vulnerable to saltwater intrusion. The majority of drinking water comes from government-owned hand pump-equipped tube wells. But during the summer season, many of these tube wells yield significantly less water. Hence, in the current scenario, water quality assessment has become important to the quantity available. Total of 31 samples of deep tube wells (groundwater) are collected at variegated locations during pre-monsoon season throughout Sagar, and then, the physical and chemical quality parameters of these water samples are analysed. Furthermore, a multivariate statistical technique is executed with the aid of the SPSS program. The hydro-chemical parameters that are taken into account for the quality analysis are pH, salinity, electrical conductivity (EC), total dissolved solids (TDS), total hardness, aluminium, arsenic, bi-carbonate, cadmium, iron, chloride, copper, chromium, cobalt, lead, magnesium, manganese, nickel, potassium, sulphate, zinc, and sodium. Then, the analysed data evaluates the water quality index (WQI). Five components are identified through the principal component analysis (PCA) technique, and 82.642% total variance is found. The outcomes of the quality assessment study illustrate that about 54.84% of collected samples come in the "excellent" water quality class when calculated by the "weighted arithmetic WQI method," and 90.32% of collected groundwater samples come in the "good" water quality class when computed using the "modified weighted arithmetic WQI method." This study helps for the interpretation of WQI to assess groundwater quality.

Probabilistic modelling is superior to deterministic approaches in the human health risk assessment: an example from a tribal stretch in central India

This case drew national attention in 2018. About 100 people died and more than 300 hospitalized in a span of few years in a village of 1200 people in a tribal stretch in central India. Medical teams visiting the area reported severe renal failure and blamed the local eating and drinking habits as causative factors. This human health assessment based on geochemical investigations finds nitrate (NO3-) and fluoride (F-) pollution as well in village's groundwater. Both deterministic and probabilistic techniques are employed to decipher the contamination pathways and extent of contamination. Source apportionments of NO3- and F- and their relationship with other ions in groundwater are carried out through chemometric modelling. Latent factors controlling the hydrogeochemistry of groundwater too are explored. While hazard quotients ([Formula: see text]) of the chemical parameters ([Formula: see text] and [Formula: see text]) identify ingestion as the prominent pathway, the calculated risk certainty levels (RCL) of the hazard index (HI) values above unity are compared between the deterministic and probabilistic approaches. Deterministic model overestimates the HI values and magnify the contamination problems. Probabilistic model gives realistic results that stand at infants ([Formula: see text] = 34.03%, [Formula: see text] = 24.17%) > children ([Formula: see text] = 23.01%, [Formula: see text] = 10.56%) > teens ([Formula: see text] = 13.17%, [Formula: see text] = 2.00%) > adults ([Formula: see text] = 11.62%, [Formula: see text] = 1.25%). Geochemically, about 90% of the samples are controlled by rock-water interaction with Ca2+-Mg2+-HCO3- (~ 56%) as the dominant hydrochemical facies. Chemometric modelling confirms Ca2+, Mg2+, HCO3-, F-, and SO42- to originate from geogenic sources, Cl- and NO3- from anthropogenic inputs and Na+ and K+ from mixed factors. The area needs treated groundwater for human consumption.